Slack adjuster for railway car brakes



Feb. 21, 1933. R. w. BURNETT SLACK ADJUSTER FOR RAILWAY CAR BRAKES Filed Jan. 14. 1929 2 Sheets-Sheet 1 Feb. 21, 1933. R w BURNETT 1,898,029

SLACK ADJUSTER FOR RAILWAY CAR BRAKES Filed Jan. 14, 1929 2 Sheets-Sheet 2 Patented Feb. 21, 1933 RICHARD XV BURNETT, OF CHICAGO, ILLINOIS SLACK ADJUSTER FOR RAILWAY OAR BRAKES Application filed January 14, 1929. Serial No. 332,552.

UNITED STATES PATENT OFFICE My invention" relates to'slack adjusters for railway car brakes.

The principal object ofthe invention is to provide asimple and inexpensive device which may be so positioned in: the brake riggingof a railway car thatnthe' slack the rigging may be readily and convenlently taken up without exposing the workman to bodily injury and without changing the 19 limits of the normal travel of the air piston and hand brake pull-rod;

It is often necessary to adjust the slack in the brake rigging of a railway car while the car is in train or under such other conditions that expose the workman to severe bodily injury. It is highly desirable that meansbe provided whereby the'sl'a'ck of the brake rigging may be taken up without requiring the workman to go-between or under the carsto effect such adjustment. My inventionaims to meet the above condition by providing a positive operating and inexpensive sla'ck adj ustin'g means which may be operated by the workman while'standing at the side of the car.

A more specific object is to provide a slack adjuster oftheabove character adapted to be interposedin a connecting rod or otherwise cooperate with the various parts of the-brake rigging, as'to vary the angularity of the various brake leversto compensate for the wear'of the brake shoes, and other parts of the rigging. In this connection'I contemplate as a specific embodiment, the-provision of a threaded member positioned beneath the car and adapted to be so operated from the side ofthe' car as to change the angularity of the brake levers, the operating means being preferably but not necessarily in the 49 form of a pawl and ratchet mechanism normally held by gravity in a position suitable for operation.

A further and more specific object is to provide a threaded member ad.ptedto be interposed in a rod of the brake rigging,

whereby the effective length of said rod may be increased or shortened asmay be desired and which is so formed as to provide a closed pocket, preferably a lubricant 50 chamber, into which the endsof the threaded rods extend. The invention also contemplates the provision of sleeve shields which extend over substantially the entire threaded end portion of the rod so as to prevent the threaded portions from being burred or otherwise damaged.

The invention consists in the novel constructions, arrangements, and combination of parts hereinafter described and claimed for carrying out the several objects above enumerated and for attaining such'other objects as will appear from the following specification.

Fig; 1' is a plan view of a railway car under frame illustrating the brake rigging and one preferred arrangement of my improved slack adjuster.

Fig. 2 is a side view of the construction shown in Fig. l.

Fig. 3 is a fragmentary plan viewillustrati ng the same general arrangement of the slack adjuster together with the construction of the slack adjuster device.

Fig. f isa side view of the embodiment shown in Fig. 3.

Fig. 5*is an end view of the'embodiment shown in Figs. 3 and 4L illustrating the normal position of the operating lever and showing also the particular form of ratchet teeth employed.

In the drawings, I have shown one embodiment of the invention applied in a preferred location in the brake rigging of a railway car. The particular type of brake rigging shown is selected merely for convenience of illustration and it will be understood, therefore, that the slack adjuster may be usedon any of the various brake riggings now in use on railway cars.

The brake rigging herein shown may be described generally as consisting of a truck dead'lever 10, a truck live lever 11, operatively connected by means of rods12'and 18 to the cylinder lever 1a. The lever let is connected at one end to the cylinder push rod 15 so that longitudinal movement of the push rod will impart longitudinal movement to the rods 12 andlS. A rod l6 connects the lever 14 with the floating lever '17 This lever is fulcrumed at one end to a bracket 18 and is connected by means of the rod 13 to the truck live lever (not shown) at the other end of the car.

The outward movement of the cylinder push rod changes the angular position of all of the levers gbove mentioned in the brake rigging and consequently forces the brake shoes 19 and 20 into frictional engagement with the car wheels.

The portion of the brake rigging associated with the hand brake consists of a lever 21 pivoted at one end to the car and connected to the cylinder push rod 15 by means of a flexible connector 22. The other end of this lever is connected to the hand brake pull rod 23.

The slack in the brake rigging, when not provided with my improved slack adjuster, is taken up by shifting the fulcrum points 2425 of the truck levers l0 and 11 and by shifting one or both pins 26 of the rod 12. Such adjustment, it will be seen, exposes the workman to great danger, especially when the adjustment of the brake is required when the car is in train or when it is so located that it is not protected by safety signals. a

My improved slack adjuster is preferably inserted in the connecting rod 16 so that it will be readily accessible for operation without making it necessary for the workman to get under the car.

The body portion of the slack adjuster is in the form of a tube provided at locations spaced from each end with threaded portions 41 and 42. The threaded portion of a short rod 43 engages the threads 41 of the body and is formed with an eyelet for engagement with the clevis portion 44 of the rod 16 The rod 16 of the brake rigging is ordinarily made of one inch stock, whereas it is desirable to employ a somewhat heavier body 43 in which the screw threads are cut for engagement with the threaded portion of the adjuster body. When the adjuster is applied to new brakes, the rod 16 may be made of stock of the appropriate diameter to accommodate the screw threads without unduly weakening the rod. However when it is applied to brakes now in service, the rod 16 may be cut and the clevis portion reattached to the bar so as to provide a suitable connection with the short rod 43 as illustrated in Figs. 3 and 4. The threaded portion 42 of the adjuster body receives the screw threads of the shank portion 45 of the clevis member 46 which connects, in the usual manner, with the floating lever 17 of the brake rigging. This latter end of the adjuster body is formed with a ratchet wheel 47 provided with squared teeth 48. An operating lever 49 formed with a relatively long hub portion 50 is swingingly supported on the hub portion 51 of the adjuster body at one side of the ratchet wheel 47. The hub portion 51 is preferably upset as indicated at 52 to lock the operating lever 49 in its applied position. The operating lever 49 carries a weighted pawl 53, the toothed end 54 of which is held in engagement with the ratchet gear 47 by means. of the weighted end 55 of the pawl. An operating rod 37 for operating the lever 49 extends to a position at the side of the car, the end 38 of the rod being bent over to provide a hand hold. It will be seen that with this construction, pulling movement of the operating rod 37 will so rotate the body portion as to move the screw threaded portions of the members 43, 45 toward each other and consequently shorten the effective length of the rod 16 between the levers 14 and 17 of the brake rigging. As soon as the operatin rod 37 is released, the operating lever wifi drop by gravity to the vertical position shown in Fig. 5. When it is desired to increase the slack in the brake rigging, for example when new brake shoes are being applied, the toothed end 56 of pawl 53 may be engaged with the ratchet wheel 47 so that a reverse movement may be imparted to said adjuster body by an appropriate oscillation of the operating lever 49. The toothed end 56 of the pawl 53 will of course be raised manually and held in engagement with the teeth of the ratchet wheel.

The closed construction of the adjuster body 40 protects the inner ends of the threaded members from corrosion, and provides a chamber 40 for a suitable lubricant. The unthreaded end portions of the body extend over the thread portions of the rods 43-45 so as to provide cylindrical shields for the threads.

I claim:

1. In a slack adjuster for the brake rig ging of a railway car, the combination with the floating and cylinder levers of said rigging, of a sectional connector for connecting said levers comprising a rod pivotally attached to one lever, a rod pivotally at-, tached at one end to the other lever and formed at the other end with a clevis, a shorter rod, of greater diameter than the last mentioned rod, pivotally attached to the last mentioned rod and provided at its other end with screw threads, a turn buckle connecting the'threaded end of the last mentioned rod with the rod first above mentioned.

2. In a slack adjuster for the brake riggin of a railway car, the combination with the floating and cylinder levers of said rigging, of a sectional connector for connecting said levers comprising arod pivotally attached to one lever, a rod pivotally attached at one end to the other lever and formed at its other end with a clevis, a shorter rod, of greater diameter than the last mentioned rod, pivotally attached to said last named RICHARD W. BURNETT. 

